Motion compensated prediction technology is occasionally used in video encoding and video decoding. In the motion compensation technology, a frame of a processing target in a video sequence is divided into a plurality of partitions. These partitions are sequentially selected as a partition of a processing target (target partition). A motion vector is then determined for the target partition. In the motion compensated prediction technology, a motion vector predictor is determined using motion vectors of neighboring partitions to the target partition and the motion vector of the target partition is predictively encoded or predictively decoded in some cases.